Radio frequency animal tracking system

ABSTRACT

The invention is directed to an improved RFID system. The system provides a transponder that can communicate over at least two different frequencies so that the real time performance of the transponder can be improved without losing backwards compatibility. The system provides an improved apparatus and method that allows the end user to customize and program identification tags. The system also provides an ear tag, which may be in button form, for use on livestock with superior durability and overall performance in the field.

RELATED APPLICATIONS

This application claims the benefit of U.S. Provisional PatentApplication Ser. No. 60/629,013, filed Nov. 17, 2004; Ser. No.60/706,645, filed Aug. 9, 2005; and Ser. No. 60/722,138, filed Sep. 30,2005, all of which are hereby incorporated by reference for all theyteach.

FIELD OF THE INVENTION

The invention relates to a radio frequency identification system andmore particularly to a radio frequency identification system fortracking animals.

BACKGROUND OF THE INVENTION

Radio frequency identification (RFID) systems are well known. RFIDsystems are either active systems wherein the transponder includes itsown power source or passive systems wherein the transponder receives itspower from a base station. Since passive RFID systems do not requiretheir own power source they are generally smaller, lighter, and cheaperto manufacture than active RFID systems. Consequently, passive systemsare more commonly employed in RFID systems for the purpose of trackingas compared to active systems.

Passive RFID systems are generally either inductively coupled RFIDsystems or capacitively coupled RFID systems. The present disclosure isapplicable to both types of passive systems; however, the presentdescription focuses on inductively coupled systems because they arepresently more common due to the fact that they have a greater effectiverange than capacitively coupled systems. Passive inductively coupledRFID systems typically include a transponder that has a microprocessorchip encircled by, and electrically connected to, a metal coil thatfunctions as an antenna as well as an inductance element. The metal coilreceives radio frequencies from a base station and generates anelectrical current that powers the microprocessor, which is programmedto retrieve stored data such as an identification number and transmitthe data back to the base station.

Standard transmission frequencies have been established for RFID tagsbased upon their field of use. For example, 13.56 MHz is a standardradio frequency used for tracking manufactured goods, whereas 400 kHz isa standard radio frequency used for tracking salmon as they travelupstream to spawn. The standard radio frequency used for identificationtags for livestock and other animals is currently 134.2 kHz. Thisrelatively low radio frequency is advantageous because it caneffectively penetrate water-containing objects such as animals. On theother hand, the frequency does not have a high transmission rate.Therefore, current RFID systems do not work well where fast datatransmission is required, such as in certain real time trackingapplications of fast moving objects. More particularly, due to theinherent signal transmission delay associated with current RFID systemsoperated at 134.2 kHz, current systems cannot in certain circumstanceseffectively query and retrieve identification numbers, also commonlyreferred to as identification codes, from identification tags as theanimals move rapidly past a particular point in space, such as whencattle move along a cattle chute commonly found at auctions ordisassembly plants. Accordingly, an improved RFID system with fasterdata transmission capabilities is desirable.

Unique challenges are associated with tracking livestock. In view ofdeadly livestock diseases such as Bovine Spongiform Encephalopathy morecommonly known as Mad Cow disease, which have been known to infect herdsand meat products, there is a strong global public interest in trackinglivestock. As such, tracking livestock is increasingly becoming morecommon as well as highly regulated. One common means to track livestockrequires livestock ranchers to apply for government-issued livestockidentification numbers, which are forwarded to designated RFID tagmanufacturers to be written into identification tags that aresubsequently packaged and sold to the end user through authorizeddistributors. This complex multi-layered and multi-stepped process ofmanufacture and distribution is inefficient and costly. Accordingly,streamlining the process by providing a method and apparatus formanufacturing and/or processing the tags is desirable.

In addition, current identification tags manufactured according to theabove outlined processes are typically not customizable by the end usersand generally include only a stored identification number. Hence, if theproducer wishes to track other data, the data must, for example, bestored on a separate computer and electronically associated with anidentification number. This limitation may necessitate carrying acomputer out in the field, which can be inconvenient and impractical. Inaddition, once the livestock changes hands, the new livestock handlermay not have access to the data that is associated with theidentification number because the data is not transferred to the newhandler. Instead, the data must be stored on a network or otherwisedeliberately made available to the new handler. Furthermore, currentidentification tags are not generally adapted to be used to measurephysical parameters of the animals such as the animal's internaltemperature, which can be helpful in determining if the animal is ill.Accordingly, it is desirable to developed an RFID system where thelivestock handler can customize the identification tag; where data inaddition to an identification number can be stored in the tag itself;where the livestock handler can use the tag to track physical parametersof the livestock in real time; and/or where the system remainscompatible with current base stations.

SUMMARY OF THE INVENTION

The invention is directed to an improved RFID system, methods of usingthe system, and methods of making the system. In an embodiment, thesystem includes a transponder that can communicate over at least twodifferent frequencies. Such an embodiment can provide improved real timeperformance of the transponder without losing backwards compatibility.In an embodiment, the system includes an improved apparatus and methodthat allows the end user to customize and program identification tags.The invention includes the tags including user provided data in printand/or in electronic form. In an embodiment, the system can provide anear tag for use on livestock that exhibits advantageous performance inthe field, shelter, and/or plant.

According to one embodiment, a radio frequency identification (RFID) tagfor identification of animals includes a first antenna and a transpondercoupled to the antenna. The transponder includes a first transmissionunit, first memory and first power circuitry. The first power circuitryis configured to receive a current induced in the first antenna, and topower the first transmission unit and first memory. The firsttransmission unit is configured to retrieve data stored in the firstmemory and to transmit at least a portion of the data via the firstantenna on a first carrier frequency and on a second carrier frequency.

According to another embodiment, a method of manufacturing a radiofrequency identification (RFID) tag, for identification of animalsincludes providing a substrate, and disposing a first coil upon thesubstrate. A first integrated circuit is coupled to the first coil. Afirst material is formed atop the first coil and first integratedcircuit. A second material is formed over the first material.

According to yet another embodiment, a method of collision preventionfor radio frequency identification (RFID) tags for identification ofanimals includes assigning each of a plurality of RFID tags a delayvalue. Each RFID tag is configured to receive a query from a basestation, and to respond thereto by waiting for a duration of timecorresponding to the delay value. Then, a response transmission isprovided. The response transmission includes a unique identificationnumber identifying an animal associated with the tag.

According to yet another embodiment, a method of providingidentification of an animal includes receiving a query from a basestation with a radio frequency identification (RFID) tag in an animal.The query is responded to with a first transmission on a first carrierfrequency and a second transmission on a second carrier frequency.

According to yet another embodiment, a method of identifying an animalto a base station with a radio frequency identification (RFID) tagincludes providing the base station with a smallest identificationnumber assigned to any of a plurality of RFID tags associated with aplurality of animals. A query from the base station is received with anRFID tag in the animal. The RFID tag being is a unique identificationnumber. The received query is responded to with a reply transmissionincluding an abbreviated identification number, which is the differencebetween the unique identifying number and the smallest identificationnumber.

According to yet another embodiment, a system for identifying animalswith radio frequency identification (RFID) tags includes a first basestation configured to operate at a first carrier frequency. The systemalso includes a second base station configured to operate at a secondcarrier frequency. The system further includes a plurality of RFID tagseach associated with one of a plurality of animals. Each RFID tag isconfigured to respond to a transmission on a first carrier frequencywith a response transmission on the first carrier frequency and aresponse transmission on a second carrier frequency. At least one of theresponse transmissions includes a unique identification number.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are incorporated in and constitute apart of the description, illustrate several aspects of the invention andtogether with the detailed description, serve to explain the principlesof the invention. A brief description of the drawings is as follows:

FIG. 1 is a diagrammatic illustration of a known RFID system commonlyused to track livestock.

FIG. 2 is a diagrammatic illustration of an RFID system according to theprinciples of the present invention.

FIG. 3 is a diagrammatic illustration of a portion of the manufacturingof the identification tag of the RFID system of FIG. 2.

FIG. 4 is a diagrammatic illustration of a top view of a strip ofidentification tags of FIG. 3.

FIG. 5 is a diagrammatic illustration of the finishing process of theidentification tag of the RFID system of FIG. 2.

FIG. 5A is a flowchart showing an operational flow for customizing andfinishing a strip of tags in accordance with the principles of thepresent disclosure.

FIG. 6 is a front elevation view of an identification tag according tothe principles of the present invention.

FIG. 7 is a schematic diagram of an alternative embodiment of asubstrate on which identification tags according to the presentinvention may be formed.

FIG. 8 is a schematic diagram of an encoding device for use with theidentification tags of FIG. 7.

FIG. 9 is a schematic diagram of a forming device for formingidentification tags upon the substrate of FIG. 7.

FIG. 10 is a perspective view of a printing device for printing onto theidentification tags of FIG. 7.

FIG. 11 is a perspective view of a second embodiment of a printingdevice for printing onto the identification tags of FIG. 7.

FIG. 12 is a representation of communication between the printing deviceof FIG. 11 and a remote database.

FIG. 13 is a schematic diagram of animals tagged with an identificationtag moving through a chute adjacent a transceiver.

FIG. 14 is a depiction of a transport vehicle unloading animals forentry into a facility.

FIG. 15 is a depiction of an exemplary method of reducing interferencebetween RFID tags.

FIG. 16A depicts an exemplary embodiment of a data frame transmittedfrom an RFID tag to a base station.

FIG. 16B depicts an exemplary embodiment of a data frame transmittedfrom an RFID tag to a base station.

FIG. 17A is a profile depiction of an exemplary embodiment of abutton-style RFID tag.

FIG. 17B is a bottom-view of the button-style RFID tage depicted in FIG.17A.

FIG. 18 is a schematic block diagram of an animal tag in accordance withthe principles of the present disclosure.

DETAILED DESCRIPTION OF THE INVENTION Definitions

As used herein, the term “animal” refers to macroscopic animalsincluding vertebrates. Animals include domesticated animals, such aslivestock and companion animals, and wild animals, such as game animalsor fish. Livestock include animals such as swine (pig), piglet, sheep,lamb, goat, bovine (e.g., cow), fish and (e.g., salmon), birds (e.g.,chickens, ducks, and geese). This list of animals is intended to beillustrative only, and should not limit the scope of any of thefollowing disclosure related to the present invention. As used herein,the term “track” refers to the identification, location, recording, andmonitoring of animals or other objects of interest, for whatever purposeor reason. This definition is illustrative of uses of the presentinvention and is not intended to limit the scope of any of the followingdisclosure related to the present invention.

The Present Tag, Method, and System

An identification tag for an animal, the tag including a first circuitincluding a memory subunit, a power subunit, and a first transmitsubunit, the subunits electrically connected to each other. The tag alsoincludes a second circuit including a second transmit subunit, thesecond circuit electrically connected to the first circuit, and anantenna connected to the first circuit. The power subunit of the firstcircuit is configured to generate an electrical current when a radiosignal is received by the antenna, and delivers this current to thefirst transmit subunit. The first transmit subunit is configured totransmit a first signal at a first frequency when it receives electricalcurrent from the power subunit, the first signal encoding at least afirst portion of any data within the memory subunit. The second circuitis configured to transmit a second signal at a second frequency when itwhen it receives electrical current from the power subunit, the secondsignal encoding at least a second portion of any data within the memorysubunit.

A method of making an identification tag for an animal includingproviding a producer of animals, at least one animal, an animalidentification tag with a data transponder and a memory storage, and atag printer located adjacent a space for confining the at least oneanimal. At least one registration code is acquired to be assigned to theat least one animal. The at least one registration code is input to thetag printer. The animal is positioned in the confined space adjacent thetag printer. The animal identification tag is positioned within the tagprinter. The registration code is printed on an exterior of the animalidentification tag. The registration code is written into the memorystorage of the animal identification tag. The animal identification tagis removed from the machine and attached to the animal.

An animal identification tag includes a flexible substrate includingupper and lower portions. A substantially rigid transponder mount ispositioned between the upper and lower portions. A transponder ismounted to the transponder mount. The transponder includes a data memorystorage, an antenna, power circuitry and transmission circuitry. Thepower circuitry is configured to generate electrical current when afirst radio signal at a first frequency is received by the antenna. Thetransmission circuitry is configured to transmit at least a portion ofany data within the data memory storage at a second frequency, and totransmit at least a portion of any data within the data memory storageat a second frequency when electrical current is received from the powercircuitry. A mounting opening extends through the upper and lowerportions and a mounting opening reinforcement mounted between the upperand lower bodies adjacent the mounting opening.

A device for making animal identification tags including a housing witha path along which an animal identification tag may be positioned. Adata writing apparatus is located within the housing adjacent the pathand positioned to write digital information to a data storage of theanimal identification tag. A printing device is located within thehousing adjacent the path and positioned to print information on anexterior of the animal identification tag. An optical scanner is locatedwithin the housing and positioned adjacent the path to optically scanthe printed information on the exterior of the animal identificationtag. A radio frequency generator and receiver is located within thehousing and positioned adjacent the path to query the digitalinformation written into the data storage of the animal identificationtag.

A method of tracking livestock includes registering an identificationcode with a central database, wherein registering includes associatingthe identification code with a user name. A passive radio frequencyidentification tag is provided. The identification code is written tothe passive radio frequency identification tag. Subsequently additionaldata is written to the passive radio frequency identification tag.

A method of tracking livestock including registering an identificationcode with a central database, wherein registering includes associatingthe identification code with a user name. A passive radio frequencyidentification tag is provided. The identification code is written tothe passive radio frequency identification tag at a physical locationwhere an animal to be tracked is located.

A method of tracking livestock including registering an identificationcode with a central database, wherein registering includes associatingthe identification code with a user name. A passive radio frequencyidentification tag is provided. The identification code is written tothe passive radio frequency identification tag. The passive radiofrequency identification tag is queried using a first frequency andtransmits a response at a second frequency.

A radio frequency identification tag includes a flexible substrate and atransponder position within the flexible substrate. The transponderincludes a passive inductance radio frequency device positioned within asubstantially rigid housing.

The present invention includes an animal, the animal including coupledto an appendage (e.g., an ear) a tag according to the present invention.

Illustrated Embodiments

Referring to FIG. 1, a conventional RFID system 10 is shown. Theconventional RFID system 10 includes a base station 12, also commonlyreferred to as a reader, and a transponder 14, also commonly referred toas an identification tag. In the depicted RFID system 10, thetransponder 14 and base station 12 are configured to be used to tracklivestock. In particular, the base station 12 and transponder 14 areconfigured to transmit and receive radio waves at the current industrystandard for RFID livestock tracking, which is 134.2 kHz. The basestation includes a transceiver 16 that emits a radio signal 18, whichmay be received by the transponder 14. The transponder 14 includes awire loop antenna 20 constructed of metal. The wire loop antenna 20receives the signal 18 and functions as an inductor to generate anelectric current from the signal 18. The generated electric currentpowers the semiconductor chip 22, which is programmed to retrieve astored identification number/code and convert the number into a signal24 that is transmitted back to the transceiver 16 in the base station12. In the embodiment shown, the transponder 14 includes a substantiallyrigid housing 26 that protects the wire loop antenna 20 from bendingwhich would likely otherwise impede or destroy the wire loop antenna's20 ability to perform. In some embodiments, the housing may be made inthe form of a plastic disk and include a hole that is sized to receive afastener for attaching the housing 26 directly to the ear of an animal.

A conventional RFID system 10 like the one described above may performpoorly in identifying animals if they move rapidly past a point inspace, such as a gate at a cattle ranch. The conventional RFID system 10may perform poorly due to the length of time between the sending of thesignal 18 from the base station 12 and the receipt of the return signal24 at the base station 12. During this time the animal can move, therebymaking it difficult to associate the received number with the correctanimal. During this time the animal may even move out of thecommunication range of the base station 12. This task of identifyinganimals in a dynamic environment is especially difficult when there areother animals of similar appearance nearby. Increasing the overallfrequency of transmission, which can increase data transmission rates,presents one way to decrease the time period and improve the systems.However, such a change would require establishing a new industrystandard and might also render all the existing systems and componentsthereof useless.

Referring to FIG. 2, a first embodiment of an RFID system 30 accordingto the present invention is shown. In the depicted embodiment the RFIDsystem 30 includes a base station 32 and a transponder 34. The basestation 32 includes a first device 36 for transmitting and receivingsignals at a first frequency 38 and a second device 40 for transmittingand receiving signals at a second frequency 42. In an embodiment, thefirst frequency 38 can be the standard frequency of 134.2 kHz and thesecond frequency 42 can be a higher frequency than the first frequency38. The transponder 34 includes an antenna, e.g., a wire loop antenna44, that is configured to receive and transmit on the first frequency38. The depicted wire loop antenna 44 is made of metal and alsofunctions as an inductor to generate an electrical current for poweringa first semiconductor chip 46. The first semiconductor chip 46 can beprogrammed to retrieve a stored identification number and transmit thatidentification number back to the first device 36 of the base station 32over the first frequency 38. In addition, the first semiconductor device46 can be programmed to transmit the identification number back to thesecond device 40 of the base station 32 over the second frequency 42 viaa second antenna 48. This alternative mechanism for transmitting back tothe base station can decrease the response time of the RFID system 30.At the same time, the RFID system 30 can be configured to remaincompatible with existing systems that operate at lower frequencies.

In the depicted embodiment, the transponder 34 further includes a secondsemiconductor chip 50 that is electrically connected to the firstsemiconductor chip 46. The second semiconductor chip 50 is shown poweredby the current generated by the metal wire loop antenna 44. The secondsemiconductor chip 50 may be configured to transmit a signal at secondfrequency 42. In some embodiments, the second semiconductor chip 50 isconfigured so that the first semiconductor chip 46 of the RFID system 30is very similar or even identical to the semiconductor chip 22 of theknown RFID system 10.

Still referring to FIG. 2, in the depicted embodiment the second chip 50may include a writeable memory device for storing customizableprogrammable data. Second semiconductor chip 50 can store any of avariety of data about an animal. For example, the health history,genetic characteristics, the date and location of sale, as well as otherdata may be stored on the second semiconductor chip 50. Alternatively,such data can be written to a data storage location of the firstsemiconductor chip 46. This data from the first semiconductor chip 46could be transmitted to the base station 32 at the second higherfrequency via the second semiconductor chip 50. Alternatively, thecustomizable programmable data can be transmitted to the base station 32at the first frequency via the first semiconductor chip. The secondfrequency 42 can be beneficial when the medium of transfer is air, whichallows for higher frequency rates and, consequently, faster rates oftransfer than other materials such as water or cement.

In the various embodiments herein, the communication link(s) (e.g.,communication links 38 and 42) may be conducted in either half duplex orfull duplex. Thus, in the context of a half duplex embodiment, a basestation, such as the base station 32 depicted in FIG. 2, may transmit arelatively low frequency carrier (e.g., 134.2 kHz) to the transponder34, thereby transferring power to its internal circuitry. Thetransponder 34 is configured to receive energy during this period, butto delay its return transmission(s), until the base station 32 ceasestransmission. After having transferred energy to the base station 32,the base station 32 ceases its transmission, and enters a period whereinits transceiving devices 36 and 40 attempt only reception of data.During this period, the transponder 34 may respond with one or morereturn transmissions. For example, the transponder 34 may simultaneouslyreturn transmission on both high and low frequency carriers 38 and 42.Alternatively, the transponder 34 may divide this period into twotimeframes—a first timeframe, during which transmission on the lowfrequency carrier 38 is performed, and a second timeframe, during whichtransmission on the high frequency carrier 42 is performed. In the wakeof having received a return transmission, the base station 32 mayre-enter its energy transfer phase, thereby beginning the cycle anew. Incontrast, in the context of a full duplex embodiment, transmissions toand from a base station, such as base station 32, and a transponder,such as transponder 34, occur simultaneously.

Full duplex schemes exhibit the quality of permitting a greater quantityof data to be communicated in a given interval of time. For this reason,under certain circumstances, full duplex embodiments may be desirable.On the other hand, half duplex systems may allow for a more reliablereturn communication from a transponder. In certain environments, thesignal emanating from the base station may reflect off of one or moresurfaces, and return to the base station. In such a circumstance, if thecommunication was conducted in full duplex, the base station would alsobe receiving a return transmission from the transponder, meaning thatthe reflected signal and the return transmission would interfere withone another. A half duplex system reduces such interference by delayingreturn transmissions until the base station is no longer transmitting(when the base station ceases transmission, it ceases to emit signalsthat can be reflected back to itself, causing the unwantedinterference). Half duplex systems possess other advantages in terms ofsimplicity and cost, as well.

In alternative embodiments, the second semiconductor chip 50 can beconfigured to communicate with an implanted biosensor, which can detecta physical characteristic including, for example, the animal'stemperature and/or blood characteristics. Such a sensor may beintegrated with transponder 34 or may be separately implanted inside theanimal. In embodiments where the transponder 34 is separate from thesensors, the sensors may communicate with transponder 34, which in turncommunicates with the base station 32. In such embodiments, the data canbe sent back to the base station 32 for analysis via the first frequency38 from the wire loop antenna 44 or the second frequency 42 from thesecond antenna 48. Depending on the surrounding conditions, the first orsecond frequency may be preferred. For example, if only air separatesthe transponder 34 and the base station 32, the faster, higher frequencymay be preferred because of the fast transmission rate, whereas if thereare cement walls or other solid or water-containing objects between thebase station 32 and the transponder 34, then the lower frequency may bepreferred due to its ability to penetrate objects. Alternatively, itshould be appreciated that the biosensors could also communicatedirectly with the base station 32.

The transponder's 34 ability to store more data than an identificationnumber can be beneficial because, for example, a tagged animal is oftenhandled or processed by a number of different individuals. Ensuring thateach individual has access to the data associated with the animal whenthe data is stored remotely from the animal can be difficult andexpensive. However, when the data in the RFID system 30 is stored on thesemiconductor chip 50 that is attached to the animal, the handler of theanimal can gain access to the relevant information about the animal.

Still referring to FIG. 2, the transponder 34 is shown as an embodimentof an identification tag 52 configured to attach to an animal. The tagcan be configured to attach to any of a variety of parts of an animal,such as to a wing, leg, ear, fin, flipper, tail, or any other suitableappendage or portion of the body of the animal or object to be tracked.In an embodiment, identification tag 52 is configured to attach to theear of an animal, for example, an ear of a cow. The identification tag52 is shown to include optional protective housing 54 and optionalgrommet 56 that are contained and/or sealed within a flexible outershell 59. In an embodiment, the protective housing 54 houses the wireloop antenna 44. The protective housing 54 in the depicted embodimenthouses the wire loop antenna 44, the second antenna 48, and the firstand second semiconductor chips 46 and 50, respectively. In thisembodiment, the protective housing 54 is designed to protect theelectronic components of the transponder 34 from damage as a result ofphysical trauma such as bending or crushing. The protective housing 54is, thus, generally at least semi-rigid. In some embodiments, thehousing may be made in the form of a plastic disk and include a holethat is sized to receive a fastener for attaching the housing 54directly to the ear of an animal.

In the depicted embodiment, the identification tag 52 is constructed tobe connected to the animal's ear with a fastener. The grommet 56prevents the area of the identification tag 52 that engages the fastenerfrom ripping or tearing due to concentrated physical stresses at thepoint of engagement. The grommet 56 is shown as a tab of reinforcedmaterial. The grommet 56 can be constructed of many different types ofmaterials including, for example, metal, plastic, or nylon. The flexibleouter shell 59 of the identification tag 52 encloses the housing 54 andcan seal the protective housing 54 and the reinforced material of thegrommet 56 from the external environment. The inclusion of the flexibleouter shell 59 makes the entire identification tag 52 more likely toyield when it impacts foreign objects such as fence posts and the like.Accordingly, the arrangement including the flexible outer shell 59decreases the chance that the identification tag 52 would injure ananimal.

Referring to FIGS. 3-5, a method for manufacturing the identificationtag 52 is shown. The method may include the step of enclosing orencapsulating housings 54 within or as part of a flexible outer shell59. As an example, nip rolling 60 or laminating flexible outer shell 59around housings 54 including electronic components therein may be usedto form a strip 62 of connected identification tags 52. It isanticipated that other processes or mechanisms may be used toencapsulate or enclose housings 54 to form strip 62 and tags 52 withinthe scope of the present disclosure and the examples provided above aremerely illustrative. In the depicted embodiment reinforced material isalso laminated within the outer shell 59. The depicted method furtherincludes the step of perforating 64 the identification tags 52 so thatthey can be detached from each other by tearing the strip 62. The methodmay further include the step of punching a hole 58 in the identificationtag 52 that is sized to receive a fastener for attaching theidentification tag 52 to the ear of an animal. It should be understoodthat the method might include more or less steps. For example, in oneembodiment the hole 58 is punched in the identification tag 52 by thetool used to attach the identification tag 52 to the animal's ear. Inother embodiments the identification tags 52 are not perforated, butrather are cut with a pair of scissors before use. Furthermore, in theembodiment shown, the strip 62 is folded over itself for storage.However, it should be appreciated that the strip 62 could also be rolledover itself for storage.

Referring to FIG. 5, an apparatus and method for customizing andfinishing the strip 62 of identification tags 52 is illustrated. In thedepicted embodiment an identification tag processor 70 is shown toinclude an identification tag writer 72, a printer 74, an optical reader76, a radio frequency reader 78, and a central processing unit 80otherwise referred to as a controller. The above-identified devices ofthe tag processor 70 are shown hardwired together via wires 82.Nonetheless, it should be appreciated that the devices can be connectedwithout wires such as via infrared signaling. In addition, it should beunderstood that identification tag processor 70 may include more or lessdevices than are shown in FIG. 5. For example, in some embodiments theoptical reader 76 is omitted and the verification is done manually. Inother embodiments the identification tag processor 70 includesadditional devices such as a touch panel user interface. The functionsof the individual devices identified above are addressed in furtherdetail below.

The depicted method of customizing and finishing the strip 62 of tags 52is shown in FIG. 5A. The method includes loading (operation 84) thestrip 62 into the identification tag processor 70. The method caninclude writing (operation 86) such as with the tag writer 72 theidentification number and other data defined by the end user to thememory of the identification tag 52. The method can include printing orotherwise marking (operation 88) the outer surface of the identificationtags 52 with text, bar codes, etc, defined by the end user, such as withthe printer 74. The identification tags 52 can include any number ofdifferent kinds of markings, which can be determined at the site ofprinting by the operator of the system. For example, in the embodimentof the identification tag 52 shown in FIG. 6, the identification tag 52is marked with an ID number, the particular animal type, a bar code, andthe weight of the animal at a particular date. The other data or markingcan include, for example, the date and time that the tag is beingprinted or that the animal arrived at or departed from the facility.

Once the outer surface of the identification tag 52 is printed orotherwise marked 88, the outside marking can be verified (operation 90)by a device, such as the optical reader 76, that reads the markings andcompares the read marking to the intended markings. Such devices mayemploy, for example, well known optical character recognitiontechnology. Similarly, once the identification number or code is writtento the inner electronic components of the identification tag 52, thewriting of the identification number can be verified by a device, suchas radio frequency reader 78, that reads the identification number andcompares the read number with the number that was intended to bewritten. According to the above process, the tags are processed and theaccuracy of the processing is checked. It should be understood thatalthough the processing can be accomplished at one physical location asshown in FIG. 5, in alternative embodiments, the processing occurs indifferent physical locations and in a different order. On the otherhand, in some embodiments, the optional laminating process shown in FIG.3 is integrated with the finishing processes shown in FIG. 5 so that theidentification tag can be generated completely on site.

It is anticipated that the tag writer 72 may be configured so that aproducer or other user may be required to input each identificationnumber in turn to enable the writing of that number to the memory andprinting of the tags. Alternatively, tag writer 72, or an associateddevice connected via a network or any wired or wireless connection, maybe pre-loaded or authorized to dispense a certain set of identificationnumbers. In an operation analogous to a refillable postage meter, aproducer may request a set of identification numbers be assigned to theparticular premises in anticipation of a need to tag and identifyanimals. In such an arrangement tag writer 72 could then dispense tagsprinted and coded with those pre-loaded numbers, improving efficiency oftagging operations that may be carried out chute-side at the producer'spremises. Data entry errors may be reduced as well, improving theaccuracy of tracking of the tagged animals. When the producer hasexhausted the set of numbers that have been assigned to the tag writer72, the producer may request that a new set of numbers be approved sothat the tag writer 72 can be “refilled.”

In an embodiment of the current system the memory device in thetransponder 34 can be written only once. In certain situations this typeof system is preferred because it ensures that the identificationnumbers are not intentionally tampered with or accidentally changed oncethe card is created. On the other hand, it may be desirable that somedata stored on the identification tag be erased and rewritten. In suchembodiments, at least a portion of the memory location in theidentification tags could be rewriteable and the tags may later beprocessed again through a similar device for updating the savedinformation. In these embodiments, the memory may be configured with aportion as write-once space for storage of the identification number anda portion as rewritable for storage of other information.

Schemes 1 and 2 below schematically describe additional embodiments ofthe tag, system, and methods of the present invention.

A further embodiment of an identification tag according to the presentinvention may include a forming or molding process involving a stripsubstrate onto which are positioned various components of the tag. Sucha strip substrate 100 is shown in FIG. 7. Substrate 100 includes aplurality of mounting locations 102 onto which are positioned thecomponents of a tag in a desired order (which will be described furtherbelow). To begin forming a tag, substrate 100 is extended into a tagproduction device 104, which may be a single enclosed machine or whichmay be composed of a plurality of individual machines performing one ormore but not all of the constituent processes.

A first mounting location 102 is positioned within device 104 so one ormore wires or circuits 106 may be formed onto substrate 100. Circuits106 may include a first lead 108, a coil 110, and a second lead 112. Achip 114 may be positioned and electrically connected to leads 108 and112. Coil 110 is preferably composed of a plurality of windings of anelectrically conductive wire, and may serve as both an induction coiland a transmission antenna, as described above. A secondary antenna mayalso be laid onto substrate 100 at location 102, such as within coil110. Alternatively, coil 110 may serve as both high and low frequencytransmission antenna, so that secondary antenna is not needed. As afurther alternative, the secondary antenna could be located outside ofcoil 110 and still electrically connected to chip 114.

In an embodiment, once coil 110, leads 108 and 112, and chip 114 havebeen positioned on substrate 100 at a position 102, device 104 mayinclude a data write head 140 to digitally encode a unique identifier142 into chip 114, as shown in FIG. 8.

It is desirable that device 104 be configured to perform a dual moldoperation, such as illustrated in FIG. 9. In a dual mold operation, afirst molded material 118 is placed at location 102 about coil 110, chip114, and leads 108 and 112. First molded material 118 is sized to encasethe earlier placed components in a relatively less flexible and moredurable material, which can help maintain the integrity of thecomponents and the connections between the components. However, as it isdesirable to have a flexible tag to attach to the animal to beidentified, the entire tag is preferably not molded of this relativelyless flexible material. In a second molding process within device 104, asecond, more flexible molded material 120 is placed about and encasesfirst molded material 118. Second material 120 preferably forms thefinished size and shape of a tag 122.

Substrate 100 can be made of any of a variety of materials of sufficientstrength and flexibility to provide a workable tag. Suitable materialsinclude polyurethane, or similar flexible materials. It is anticipatedthat substrate 100 and tag 122 can include or be made of any of a widevariety of thermoactive materials. Numerous suitable thermoactivematerials are commercially available.

Suitable thermoactive materials include thermoplastic, thermosetmaterial, a resin and adhesive polymer, or the like. As used herein, theterm “thermoplastic” refers to a plastic that can once hardened bemelted and reset. As used herein, the term “thermoset” material refersto a material (e.g., plastic) that once hardened cannot readily bemelted and reset. As used herein, the phrase “resin and adhesivepolymer” refers to more reactive or more highly polar polymers thanthermoplastic and thermoset materials.

Suitable thermoplastics include polyamide, polyolefin (e.g.,polyethylene, polypropylene, poly(ethylene-copropylene),poly(ethylene-coalphaolefin), polybutene, polyvinyl chloride, acrylate,acetate, and the like), polystyrenes (e.g., polystyrene homopolymers,polystyrene copolymers, polystyrene terpolymers, and styreneacrylonitrile (SAN) polymers), polysulfone, halogenated polymers (e.g.,polyvinyl chloride, polyvinylidene chloride, polycarbonate, or the like,copolymers and mixtures of these materials, and the like. Suitable vinylpolymers include those produced by homopolymerization, copolymerization,terpolymerization, and like methods. Suitable homopolymers includepolyolefins such as polyethylene, polypropylene, poly-1-butene, etc.,polyvinylchloride, polyacrylate, substituted polyacrylate,polymethacrylate, polymethylmethacrylate, copolymers and mixtures ofthese materials, and the like. Suitable copolymers of alpha-olefinsinclude ethylene-propylene copolymers, ethylene-hexylene copolymers,ethylene-methacrylate copolymers, ethylene-methacrylate copolymers,copolymers and mixtures of these materials, and the like. In certainembodiments, suitable thermoplastics include polypropylene (PP),polyethylene (PE), and polyvinyl chloride (PVC), copolymers and mixturesof these materials, and the like. In certain embodiments, suitablethermoplastics include polyethylene, polypropylene, polyvinyl chloride(PVC), low density polyethylene (LDPE), copoly-ethylene-vinyl acetate,copolymers and mixtures of these materials, and the like.

Suitable thermoset materials include epoxy materials, melaminematerials, copolymers and mixtures of these materials, and the like. Incertain embodiments, suitable thermoset materials include epoxymaterials and melamine materials. In certain embodiments, suitablethermoset materials include epichlorohydrin, bisphenol A, diglycidylether of 1,4-butanediol, diglycidyl ether of neopentyl glycol,diglycidyl ether of cyclohexanedimethanol, aliphatic; aromatic aminehardening agents, such as triethylenetetraamine, ethylenediamine,N-cocoalkyltrimethylenediamine, isophoronediamine,diethyltoluenediamine, tris(dimethylaminomethylphe-nol); carboxylic acidanhydrides such as methyltetrahydrophthalic anhydride, hexahydrophthalicanhydride, maleic anhydride, polyazelaic polyanhydride and phthalicanhydride, mixtures of these materials, and the like.

Suitable resin and adhesive polymer materials include resins such ascondensation polymeric materials, vinyl polymeric materials, and alloysthereof. Suitable resin and adhesive polymer materials includepolyesters (e.g., polyethylene terephthalate, polybutyleneterephthalate, and the like), methyl diisocyanate (urethane or MDI),organic isocyanide, aromatic isocyanide, phenolic polymers, urea basedpolymers, copolymers and mixtures of these materials, and the like.Suitable resin materials include acrylonitrile-butadiene-styrene (ABS),polyacetyl resins, polyacrylic resins, fluorocarbon resins, nylon,phenoxy resins, polybutylene resins, polyarylether such aspolyphenylether, polyphenylsulfide materials, polycarbonate materials,chlorinated polyether resins, polyethersulfone resins, polyphenyleneoxide resins, polysulfone resins, polyimide resins, thermoplasticurethane elastomers, copolymers and mixtures of these materials, and thelike. In certain embodiments, suitable resin and adhesive polymermaterials include polyester, methyl diisocyanate (urethane or MDI),phenolic polymers, urea based polymers, and the like.

Suitable thermoactive materials include polymers derived from renewableresources, such as polymers including polylactic acid (PLA) and a classof polymers known as polyhydroxyalkanoates (PHA). PHA polymers includepolyhydroxybutyrates (PHB), polyhydroxyvalerates (PHV), andpolyhydroxybutyrate-hydroxyvalerate copolymers (PHBV), polycaprolactone(PCL) (i.e. TONE), polyesteramides (i.e. BAK), a modified polyethyleneterephthalate (PET) (i.e. BIOMAX), and “aliphatic-aromatic” copolymers(i.e. ECOFLEX and EASTAR BIO), mixtures of these materials and the like.

Whatever material is used for substrate 100, the material should becompatible with first and second molded materials 118 and 120. This willensure good adhesion of the material once they are molded together toform tag 122. It may be preferable to have substrate 100 and moldedmaterials 118 and 120 be made from different forms, durometer orhardness of the same base material, such as polyurethane. Such a commonmaterial base for all three components may help to improve bonding ofthe materials of tag 122. Another approach to improving bonding oradhesion between the materials may be to mold second material 120 aboutfirst material 118 while first material 118 is still green, meaning thatit has not fully cooled or cured. These approaches to improve bonding oradhesion may be applied separately in the formation of tag 122 or may becombined.

As described above, tag 122 may be printed upon in a later process withvarious unique identification numbers and other unique visualattributes. However, such printed markings may be susceptible to damageif they are surface markings only. Device 104 may be configured to moldin a unique identification number in an exterior surface of secondmaterial 120. Such a molded in marking 126 is less susceptible todestruction during movement of a tagged animal. Such a molding-inprocess within device 104 may be carried out with a mold imprint that isautomatically indexed for each tag 122 produced along substrate 100, sothat each tag 122 has a unique identifier compared to the other tags ofthe substrate. If sets of numbers are provided by an appropriategovernment agency, the molded in numbers can be made to correspond to ormatch the government issued numbers. Tag 122 may also include an area128 for adding a local or management identifier separate from thegovernment issued identifier.

As an alternative, or in addition, to the identifier molding processdescribed above, device 104 may also include an inkjet printer head, alaser printer head, or some form of a sublimation printer head. Thesedifferent printer heads within device 104 would provide for differentlevels of permanence and durability of markings as compared with themolding process. The print head can be employed to print, for example,the date and time that the tag is being printed or that the animalarrived at or departed from the facility. It is also anticipated thatdifferent in-mold decorating processes may be used to mark tag 122 withunique government identifier 142. Also, other methods may be used toprovide additional security for the authenticity of tag 122, such asheat stamping holograms or similar features into tag 122 during theplacement of second material 120 within the mold.

In-mold marking or labeling may be incorporated with the presentdisclosure to provide an alternative approach to forming tags 122 withdistinct visual appearances. Such in-mold marking may include theinsertion of a pre-printed mold-sized substrate within the mold andadhered to an inner surface of the mold. When second material 120 isinjected into the mold, the pre-printed substrate and second material120 would fuse or bond, durably attaching marking to the exterior of tag122 during the molding process. As alternative, substrate 100 may beused to incorporate a pre-printed exterior marking, for example, on areverse side opposite where the antenna is formed, and device 104configured to ensure that this reverse side of substrate 100 is part ofan outer surface of tag 122.

Depending on the requirements of the particular application, device 104may provide tags 122 with unique government identifier 142 and one ormore local indicia, such as color coding, or larger printed identifierssuch as, but not limited to local or management numbers 146. Such acombination of government issued identifier 142 and local managementnumber 146 would permit tag 122 to fulfill both higher level trackingand long term functions along with shorter term local functions, such astracking an animal in a feedlot or an auction facility. The localindicia can include, for example, the date and time that the tag isbeing printed or that the animal arrived at or departed from thefacility.

As described above, tag 122 is shown with a single chip 114 mounted tosubstrate 100. In this embodiment, chip 114 is capable of handling bothhigh and low frequency transmission. It is also anticipated that twoseparate chips may be mounted within each tag 122. One of the chips maymanage receipt of power induced by an external signal received throughcoil 110 and then the transmission of one of the two transmissionfrequencies. The first chip would also pass some of the induced energyfrom coil 110 to the second chip. The second chip may then transmit onthe second frequency. It may be desirable to use two separate chips toreduce overall cost of production or to improve efficiency of thetransmission or reception functions of tag 122. Alternatively, using twochips may enable more flexibility in the use of alternative embodimentsof tags, as will be described below.

As shown in FIG. 10, a string of tags 122 formed on substrate 100 ismaintained in a continuous strip 124, which may be fanfolded, rolled orotherwise packaged for sending to a producer, an auction lot, or otherlocation within the animal production process. In an embodiment, tags122 in strip 124 are inserted within a printing and encoding device 130that may be positioned chute or corral side for ease of operation. Eachof the tags 122 is pre-molded and encoded with a government issuedidentifier. Each of the tags 122 also includes area 128 for printing,embossing or otherwise marking with a local or management identifier.Area 128 allows a printing head 134 of chute side printer and encoder130 to be used to apply a specific marking immediately prior to tag 122being attached to the animal. While a novel printer/encoder embodiment130 is described and shown herein, it is anticipated that tags 122 andstrip 124 may be used with conventional printers currently in use forprinting characters or symbols within area 128.

As shown in FIG. 11, chute side printer and encoder 130 may also includean encoding head 136 to place additional digital information on chip 114that will be transmitted at the higher frequency when tag 122 is queriedwith an appropriate signal. As shown also in FIG. 12, such additionalinformation 144 could include identifiers of the producer premises,relevant dates, local control numbers or other elements. As shown inFIG. 12, chute side printer and encoder 130 may also upload certaininformation to a national database 148 to associate a particulargovernment identifier 142 with particular additional information 144.

By having tags 122 maintained in a strip 124, printer 130 may advancetags 122 automatically without requiring a user to manually insert tags.After each tag 122 is printed with a local management number 146 inprint area 128, a web 132 between each tag 122 may be severed by a finaloperation of printer 130, and a user may retrieve the tag for attachingto the animal. Having tags 122 in a specific order along strip 124ensures that a known sequence of government identifiers may be assignedto animals.

As described above, one of the unique features of tag 122 is theinclusion of two distinct transmission frequencies. In addition, thesetwo frequencies may be provided to communicate different sets of dataand they may function at different ranges or proximities to atransceiver keyed to induce power into coil 110. Differences infrequency may also be configured to provide different depths ofpenetration as balanced with signal or data density or transmissionspeed. A lower frequency signal, such as query signal 150 and replysignal 151 will be able to penetrate through relatively more materialbut will have relatively shorter range of transmission to an externaltransceiver 152, as shown in FIG. 13. Such a lower frequency signal willalso be able to transmit relatively less data over time. A higherfrequency signal 154 will provide a greater transmission distance if therange is unobstructed, though signal 154 will not be able to penetratean obstruction as well as signals 150, 151. Further, signal 154 will beable to transmit a greater amount of data over the same amount of timeto a receiver 156, as compared to signal 151.

However, since there is growing acceptance of a standard, or ISOfrequency for use with agricultural animals, such as cattle, at leastone of the frequencies transmitted by tag 122 preferably conforms to thestandard. The second, or any additional frequencies may be configured asdesired by a user or producer to accomplish other herd management orsales tasks. For example, a producer may desire to have ear tags oncattle which transmit a government issued identification number to astandard transceiver and also transmit more specific information such asdate of birth, or more specific herd information, to specializedreceiver. The government identifier is likely a required item that mustbe transmitted by tag 122, while the remaining data items are forspecific herd or sales functions.

In the previous examples of printing and encoding of tags, describedabove, the tag was printed and encoded with all data and identifiersdirectly at chute side or in a single process. This alternativeembodiment may involve two processes, one process for the creation ofstrip 124 of tags 122, each pre-encoded with a government identifier andindelibly marked with the identifier, and the other process for theprinting and encoding local management data and identifiers. It isanticipated that the first process may be performed in a high efficiencyand secure setting, which may be centralized and serve a plurality ofproducers and auction lots. The second process may take place at a userlocation, such as chute side at an auction yard or at a producer'spremises.

By having coil 110 optimized for use with a standardized ISO frequency,which is typically approximately 134.2 kHz, the induction coil can beused to provide power to both of the high and low speed transmissioncircuits. Current tags are generally arranged to receive a signal withcoil 110 at the same frequency that they transmit through coil 110. Tag122 is configured so that power is induced within coil 110 and energizesboth transmit circuits at the same time. Thus, the higher frequencytransmit capability of tag 122 does not require a separate coil 110 andthe high frequency receiver receiving the higher frequency data signalfrom tag 122 does not require a transmitter. Alternatively, transceiver152 may include receiver 156 within an integral housing such as housing158, so that a single unit may receive both the low and high frequencysignals 150, 151, and 154.

Another advantage to using two different frequencies for transmittingdata from tag 122 is that it allows more information to be gathered fromanimals 160 that may be moving quickly, for example, along a passagewayor chute 162 between pens or other holding enclosures. With the lowerfrequency signals 150, 151, the animal may be within range oftransceiver 152 for only a short time, allowing only the simplegovernment identifier to be transmitted and received, before the animalhas moved out of range. The paired use of higher frequency signal 154,with a proportionally longer range and a greater transmission speed, mayprovide a longer dwell time of the animal within the range of receiver156 and provide for the transmission of more detailed data during thisdwell time. Both of these frequencies, with their different ranges andtransmission speed, are examples of near-field communications approachesand some of the trade-offs that may exist with such approaches. Thepairing of complementary near-field communications systems within asingle tag 122 provides for a balancing of the tradeoffs withoutsacrificing conformance with a required standard or speed and density ofdata transmission.

As shown in FIG. 13, more than one animal 160 may be within range ofeither or both transceiver 152 and receiver 156 simultaneously. They maybe within chute 162, a holding pen or corral, or some other enclosure.When this occurs, a plurality of tags 122 may be trying to respond toquery signal 150, so that a plurality of signals 151 and 154 may betransmitted at the same time. In such a situation, some form ofanti-collision mechanism is desirable to reduce conflicts or collisionsamong the plurality of signals 151 and 154 being transmitted by theplurality of tags 122 so that each of the signals 151 and 154 can becaptured by transceiver 152. One embodiment of an anti-collisionapproach may be to include a switch in the higher frequency transmissionportions of circuitry 106 of tags 122 and to configure a secondtransceiver 256 in place of receiver 156. Such a switch, preferablyincluded on chip 114, would permit transceiver 256 to signal to each tagin turn when it has received the additional information 144 from thatparticular tag 122. When a tag 122 receives this acknowledgement signalfrom second transceiver 256, the tag 122 would cease to transmit itsadditional information 144. This will permit transceiver to in turnreceive and acknowledge the receipt of the additional information 144from each tag 122 in turn, until all the tags 122 within range oftransceiver 256 have ceased to transmit high frequency signals.

Such anti-collision technology could also be applied to the lowerfrequency transmission by tags 122 but is less likely to be needed, dueto the shorter range of the lower frequency transmissions. In addition,it may be desirable to ensure that tag 122 always transmits itsgovernment identifier when polled by transceiver 152.

As shown in the earlier FIGS., different antennas for each of thedifferent frequencies may be provided within tag 122. One of thetransmission antennas is shown as the same coil 110 that receives aninduction and polling signal to trigger transmission by tag 122. It isanticipated that tag 122 may include a single transmission antenna thatserves both frequencies, with coil 110 serving only as a receivingantenna. Also, the antennas shown have a generally planar layout, lyinggenerally parallel with tag 122. Such an antenna layout transmits mostefficiently in a direction perpendicular to the plane of tag 122.However, it is difficult to ensure that tag 122 will be optimallypositioned by the marked animal to place the tag in the desired plane.It is anticipated that one or both transmission antennas may beconfigured to be more omni-directional, and thus may provide a strongersignal in one or both frequencies along a broader range of directions.

It is further anticipated that tag 122 may include a powered orsemi-powered transmitter with an on-board power source, as compared tothe transmitters described above which receive induced power fromtransceiver 152 via coil 110. Such an alternative embodiment might stillbe triggered to transmit stored data through a signal from transceiver152, but the on-board power supply might provide for higher signalstrength or length of transmission than might be possible with theinduced power embodiment shown above. By semi-powered, it is intended tomean that the tag would still receive some power via induction throughcoil 110 but that more power than that induced might be available fortransmission.

There are a variety of combinations of fully- and semi-poweredtransmission capabilities that may be included within the presentinvention. It is anticipated that the two or more transmission circuitsincluded on tag 122 could transmit in distinctly different fashions, inresponse to a query signal. One of the transmission circuits couldrespond by transmitting continuously for a fixed period of time, oruntil the level of power available in a capacitor connected to thecircuit dropped below a specified level. One of the transmissioncircuits might transmit data only a specified number of times (forexample 1 to 3 times) in a burst mode only in direct response to a querysignal. This burst mode could be a higher power transmission that drawspower from an on-board capacitor or battery. Such a high powertransmission could only be supported for a limited number of operationsbefore draining the power supply so it is likely that the number ofbursts performed in response to a query signal would be smaller. It isalso anticipated that an on-board capacitor may provide a morepersistent storage of at least a partial charge, rather than dischargingentirely during transmission. If tag 122 only transmits for a specifiedperiod of time when exposed to a query signal, any remaining chargewithin the capacitor could be conserved to support future transmissions.In addition, if tag 122 remains within range of the query signal aftercompleting the specified length of transmission, exposure to the querysignal could also induce current to provide additional charge to thecapacitor.

A higher power transmission in response to a query mode could be also beaccomplished on a periodic basis when tag 122 is continuously withinrange of a query signal. Since the query signal may be used to induce anelectric current in tag 122 to power operation, if tag 122 iscontinuously in range of such a signal, the induced current could bedirected to a capacitor. When the capacitor has reached a certain levelof charge, the burst mode of transmission could be enabled. Similarly,an on-board battery could be used to provide a periodic bursttransmission but interval may be based on a clock cycle rather than acapacitor charge level. For example, while within range of the querysignal, tag 122 may transmit data in burst mode every ten minutes, orsome other pre-specified interval.

In conjunction with the collision avoidance approach described above, anon-board capacitor on tag 122 may be charged by inductance by the querysignal, even if tag 122 has been instructed to not transmit all or partof its data. It is also anticipated that an on-board battery and anon-board capacitor may be used in conjunction with one another. In suchan example, the capacitor would receive some induced current from thequery signal, which would trigger transmission of data on the multiplefrequencies of tag 122. While the charge within the capacitor may besufficient to permit transmission, the battery may be used to enhancethe power of the signal transmitted on one or more of the frequencies.Such a pairing of capacitor and battery may extend the life of thebattery by only tapping it for supplemental power to augment the powerprovided by the capacitor. Such a pairing of power sources for tag 122could provide for enhanced range of data transmission and may alsopermit tag 122 to transmit a greater volume of data.

Such added capacity for transmission data may be utilized byincorporating one or more biosensor devices, such as a core body orblood temperature sensor, located elsewhere on the animal to which tag122 is attached. It is anticipated that these biosensors could beincorporated into a local data bus for the animal and that tag 122 couldserve as a storage device or a retransmission device for data collectedand signaled by the biosensors. In such an arrangement, the biosensorswould have low level communication capabilities that would be sufficientstrong to transmit data to tag 122, which might be attached, forexample, to an ear of the animal. Tag 122 would then retain some amountof information, such as the most recent data from the biosensors, andthen transmit this data in response to a query signal. The powerrequired to transmit this additional data received from the biosensorsand held by tag 122 may make the additional transmission capacityprovided by including a persistent on-board power supply. Such apersistent power supply could be an on-board battery or a capacitorwhich maintains some residual charge after transmission and which mayrecharge itself with induced current from a query signal betweentransmissions.

It is also anticipated that the above dual process creation of animalidentification tags may be adapted to non-electronic identifier tags. Asan example, it is known to provide animals with temporary back tags oncethey arrive at an auction lot from a producer facility. These back tagsinclude basic identification of the animals and their source during andimmediately after the auction but are not intended to be permanentlyattached to the animal. Such tags may still be created with a governmentissued identifier at a central facility and shipped to the auction lotfor chute side printing with the desired local identifiers and sourceinformation that are necessary for the sale to proceed. Such tags mightonly last for a week or so, but this may be sufficient time for ananimal to pass from a producer through an auction lot, to a buyer, whoimmediately processes the animal. The government identifier wouldaccompany the animal during these transitional steps between the variousparties and be available to the processor to ensure that a sourceidentifier remains with the animal. While not having the benefit of theremote query and transmission capabilities described above, thistemporary tagging production process may satisfy regulatory requirementsfor identification of source throughout the transfer and processingfunctions.

Similarly, it is anticipated that an alternative embodiment of tag 122may be constructed without the electronics for receiving or transmittingsignals. This alternative non-electronic tag could still be created in acontinuous strip upon substrate 100 and pre-printed with a uniquegovernment identifier through a variety of in-mold or post moldinglabeling techniques described above. The tag could then be transportedchute-side, where a local identifier and/or additional informationregarding the animal, such as source, date of birth, etc, may be printedon the tag before it is affixed to the animal.

It is also anticipated that back tags may be formed according to thepresent invention which incorporate one or more of the signalingfeatures described above. Such RFID back tags may be configuredsimilarly to tag 122 or other tags described above, and includeantenna(s) and circuitry for receiving a signal at a first frequency,and responding with a signal at one or more frequencies. Such RFID backtags would not need to be encapsulated in a durable outer layer, such assecond material 120, as the back tags are not intended to be present onthe animal or object marked for an extended period of time. It may bedesirable to have these back tags include first material 118 as a moredurable, more rigid layer than current back tags, to provide some degreeof integrity protection for the antenna and circuitry as the tag isattached to the back of an animal and the animal wanders about a corralor pen at a sales or holding facility. The antenna and signal circuitrycould be mounted to substrate 100 and then overmolded with firstmaterial 118, as described above. The combination can be marked in-moldor printed on post molding to provide the external markings describedabove. This external printing may be accomplished wholly or in part atchute-side. As described above, these RFID back tags may be encodedwholly or in part at chute-side as well.

FIG. 14 depicts a transport vehicle 1400 carrying a plurality of animals(represented as circle, some of which are individually called out withreference numerals) to a facility. The animals depart from the transportvehicle through a door 1402, and are guided by fencing 1404 to thefacility (not depicted).

At the facility, the animals (e.g., cattle) may be held in variousholding areas. (The animals are referred to below as cattle for the sakeof illustration. It is to be understood that the animals may be of anyspecies.) Depending upon the transaction to be carried out at thefacility, the cattle may be segregated by ownership, size, anticipatedsize at some point in the future, etc. Thus, for example, one holdingarea may contain cattle owned by one owner, while another holding areacontains cattle owned by another owner. Alternatively, one holding areamay contain cattle of a particular size or projected size, while anotherholding area may hold cattle of another size or projected size. In anyevent, the cattle are put into various holding areas at the facilitybased upon a segregation criterion.

En route to the facility, the cattle pass through a communication zone1406. The communication zone 1406 is an area in which an RFID tagattached to a steer or heifer receives a query (i.e., a transmission ofelectromagnetic radiation at a given frequency or frequencies)transmitted from a base station 1408, as described above with referenceto FIGS. 1-13. Outside of the communication zone 1406, an RFID tag isout of range of the base station 1408, meaning that the RFID tag doesnot receive a query from the base station 1408, and does not attempt togenerate a return transmission. In FIG. 14, the communication zone 1406is depicted as being at a point removed from the truck. Of course, thecommunication zone 1406 may be located at any desired point, includingin the transport vehicle itself, at the door of the transport vehicle,or at the entry of the facility, for example.

As a steer or heifer passes through the communication zone 1406, theRFID tag associated with the animal receives a query from the basestation 1408. In response, the RFID tag replies with a communicationframe. As described previously, the communication frame may include aunique number, which identifies the animal. In addition, or as analternative, the communication frame may include the segregationcriterion used to sort the various animals into the various holdingareas within the facility. (Of course, other information may be storedin an RFID tag, and may be included in the communication frame, asdescribed previously.) Thus, as a given steer or heifer passes throughthe communication zone 1406, its identity and sorting criterion may beknown to the personnel operating the facility. For example, theinformation transmitted from a given RFID tag to the base station 1408may be presented upon a display, so that the personnel can view thedisplay as the animal passes through the communication zone 1406, andcan thereby determine to which holding area the animal should be lead.

Observation of FIG. 14 reveals some challenges. The underlying premiseof the aforementioned scheme is that when the identificationinformation/sorting criterion is presented on the display, the personneloperating the facility will be able to determine the particular animalto which the information corresponds (i.e., they mentally ask themselves“which animal just walked through the communication zone?”). Aspreviously noted, the communication zone 1408 is finite, and the cattlemay pass through the zone 1406 quickly. Thus, it is possible that thereturn transmission may not be fully processed and presented on thedisplay until the animal has already exited the communication zone 1406,and progressed toward the facility. Such an eventuality is troublesome,because confusion may arise regarding the identity of a particularanimal corresponding to the information presented on the display. Forexample, the animal may mingle with other animals, creating confusionregarding which animal had just passed through the communication zone1406. To reduce the impact of this problem, it is beneficial to reducethe duration of time between receipt of the query by the RFID tag andthe receipt of the return response and subsequent presentation on thedisplay. This issue has been addressed in one manner previously byvirtue of the aforementioned embodiments of the device that utilize ahigher carrier frequency (e.g., 13.5 MHz) and thereby carry data to thebase station 1408 at a higher data rate. As an alternative, theaforementioned duration may be shortened by reducing the amount of datathat is transmitted from a given RFID tag to the base station 1408. Anexemplary scheme for such a reduction in transmitted data is describedwith reference to FIGS. 16A and 16B (described below).

Observation of FIG. 14 reveals another challenge. As can be seen in FIG.14, more than one animal may be in the communication zone 1406 at thesame time. Consequently, as the base station 1408 transmits a query, thequery is received by each of the animals in the communication zone 1406.For example, since animals 1410-1414 are simultaneously located withinthe communication zone 1406, each of the RFID tags attached to theanimals 1410-1414 receives the query and attempts to reply with aresponse message frame. The response message frames from each of theRFID tags on each of the animals 1410-1414 may interfere with oneanother, meaning that one or more of the animals 1410-1414 may passthrough the communication zone 1406 without ever having successfullytransmitted its response message frame to the base station 1408.Therefore, there exists a need for a scheme by which tag-to-taginterference is reduced. Exemplary embodiments of such a scheme arepresented with reference to FIG. 15.

The scheme depicted in FIG. 15 operates upon the proposition that,during manufacture, or at some point thereafter, each RFID tag isencoded with either or both of a delay control value and/or a repeatcontrol value. Briefly, a delay control value is a number store in thememory of an RFID tag, or encoded in the circuitry thereof, whichdetermines a duration of time the RFID tag waits from the moment itreceives a query to the moment it replies with a response message frame.A repeat control value is a number store in the memory of an RFID tag,or encoded in the circuitry thereof, which determines a repetition rateat which a given RFID tag sends a set of N response message frames(e.g., an RFID tag replies to a query by the transmission of N responsemessage frames repeated at a rate determined by the repeat controlvalue).

FIG. 15 depicts a method by which an RFID tag may use the delay controlvalue and/or repeat control value stored/encoded therein. As can be seenfrom FIG. 15, a given RFID tag initially receives a query transmission,and is thereby energized (operation 1500). Next, as shown in operation1502, the delay control value is retrieved from memory. Thereafter, theRFID tag delays for a period of time determined by the delay controlvalue before replying with a response message frame (operation 1504).For example, the RFID tag may include a clock circuit therein (e.g., aclock circuit may be embodied within or in communication with thetransmission circuitry). The delay control value may be an integerexpressing the number of clock cycles to be witnessed by thetransmission circuitry before replying with a response message frame.Thus, turning to FIG. 14, the RFID tag associated with animal 1410 maybe assigned a delay control value causing it to delay a period of 300 msprior to generation of a response message frame, while animal 1412 maydelay for 600 ms, and animal 1414 may wait for a period of 0 ms. The netresult of the delay control values, then, is to achieve a time domainmultiplexing effect, in which each RFID tag within the communicationzone responds at a different point in time.

An RFID tag may also respond to the receipt of a query (operation 1500)by retrieving a repeat control value stored in memory, as shown inoperation 1506. Thereafter, each RFID tag may respond to the query bytransmitting a set of N response message frames with a periodicitydetermined by the repeat control value, as depicted in operation 1508.(Again, for example, the RFID tag may include a clock circuit with, orin communication with, its transmission circuitry, in order to controlthe periodicity). Thus, for example, animal 1410 may be assigned arepetition rate/periodicity of 100 ms, while animal 1412 is assigned arepetition rate of 150 ms, and animal 1414 is assigned a repetition rateof 250 ms. Thus, assuming for the sake of illustration that N=3, uponreceipt of the query, each RFID tag corresponding with animals 1410-1414replies with three identical message frames. Initially, if no delayinterval is used (i.e., if operations 1502-1504 are not used), each ofthe transmissions interferes with one another. However, during thesubsequent repetitions, each RFID tag eventually transmits a responseframe that is uninterrupted by the other repeated response frames, byvirtue of the variety of repeat control values assigned to each tag. Itis understood that the delay and repeat schemes described by operations1502-1504 and 1506-1508 may be used individually or in combination withone another (i.e., an RFID tag may be configured to both delay itsresponse, and to repeat its response at a desired rate).

One underlying premise of the foregoing schemes is that the delaycontrol values and repeat control values assigned to the RFID tagsassociated with the incoming animals exhibit a variety sufficient toachieve the goal of providing each RFID tag with a portion of timeduring which it is the only RFID tag responding to the base station. Toenhance the chances of that goal being realized, the delay controlvalues and/or repeat control values assigned to the RFID tags may bestored, so that a desired distribution of delay control values and/orrepeat control values may be enforced across a set of RFID tags. Forexample, for a given set of RFID tags, the distribution of delay controlvalue and/or repeat control values may be approximately Gaussian orconstant (i.e., “flat”).

As discussed previously, it may be desirable to reduce the amount ofdata transmitted from an RFID tag to the base station. FIGS. 16A and 16Billustrate a scheme by which such a reduction may be achieved. FIG. 16Adepicts an exemplary (simplified) embodiment of a standard message frametransmitted from a given RFID tag to a base station, upon receipt of aquery. As can be seen from FIG. 16A, the standard message frame includea header 1600, followed by 30 bits, which constitute the uniqueidentification number 1602 assigned to a particular animal, followed byan arrangement of stop bits 1604. (30 bits is sufficient to generateover one billion unique identification numbers, and is used for the sakeof illustration only. If a greater or lesser number is needed, theunique identification number may include a greater or lesser number ofbits. Also, it is to be noted that the exemplary frame of FIG. 16A issimplified in that certain well understood features of communicationframes are not depicted therein, because they are not of interest inthis context, e.g., error correction codes, parity bits, etc.)

Turning to FIG. 16B, it can be seen that a frame of lesser length mayadequately communicate the unique identification number to a basestation, if the base station is seeded with a reference number to beginwith. Consider, for example, the situation in which a set of one-hundredanimals arriving on a transport vehicle have been assigned a set ofconsecutive numbers, such as 942,056,032 through 942,056,131. In such aninstance, for example, it is unnecessary to transmit the entireidentification code. Instead, the base station may be seeded with areference number, which, in this case, may be equal to the smallestidentification number assigned to any of the animals, i.e., 942,056,032.In the wake of having seeded the base station with the referencenumeral, a given RFID tag may simply transmit the difference between theidentification number assigned thereto and the reference. For example,to communicate an identification number of 942,056,051, an RFID tag needonly transmit the binary sequence “10011.” Thus, to accommodate a set ofone-hundred animals assigned consecutive identification numbers, anoffset of only seven bits need be transmitted from any given RFID tag tothe base station. Such a message frame is depicted in FIG. 16B, visuallyrevealing that such a message frame contains fewer bits, and cantherefore be transmitted to the base station in a relatively shorteramount of time. As shown in FIG. 16B, the base station may use theoffset to determine the actual identification number assigned to theRFID tag by adding the offset to the reference:ID=Reference+Offset.

To permit execution of the aforementioned scheme, each of the RFID tagswithin assigned to a set of animals to be transported or otherwiseprocessed as a group must be informed of the reference (so that they cancalculate and subsequently transmit the offset therefrom). Further, thebase station must also be made aware of the reference. Such sharing ofthe reference may be performed manually (e.g., an individual may enterthe transport vehicle, for example, and scan each of the RFID tags witha unit programmed to identify the smallest identification numberassigned to the group. Thereafter, the individual may re-scan each ofthe tags, to program them with the determined reference, and theindividual may manually enter the reference into the base station).Alternatively, the reference may be determined automatically (e.g., thetransport vehicle may be outfitted with a system that queries each ofthe RFID tags therein to determine the smallest identification numberassigned to any RFID tag therein. Then, the system transmits thatidentification number to each of the RFID tags to use as the reference.Thereafter, upon arriving at the facility, the truck-based systemwirelessly shares this information with the base station). Of course,the aforementioned schemes for seeding the base station and RFID tagswith the reference are exemplary only. For purposes of practicing theinvention, it is necessary only that the base station and RFID tage beseeded, by whatever means.

FIGS. 17A and 17B depict an exemplary embodiment of an RFID tagfashioned in a “button style.” FIG. 17A depicts the button-style RFIDtag in profile. As can be seen in FIG. 17A, the button includes a baseportion 1700 and an axially located projecting portion 1702. A channel1704 penetrates the base portion 1700 and the projecting portion 1702.An elongated barbed “male” piece (not depicted in FIG. 17A) may extendthrough the “female” channel 1704, and fasten the button-style RFID tagto, for example, an animal's ear.

FIG. 17B is a bottom view of the button-style RFID tag of FIG. 17A. Ascan be seen from FIG. 17B, the base portion 1700 includes outer andinner circular grooves 1706 and 1708, respectively. As shown in FIG.17B, these grooves 1706 and 1708 may be coaxial. A recess 1710interconnects the grooves 1706 and 1708. During manufacture, a firstcoil antenna (not depicted) is wound around the outer groove 1706 (used,for example, for reception and transmission on a relatively low carrierfrequency, such as 134.2, kHz), and a second coil antenna (also notdepicted) is wound around the inner groove 1708 (used, for example, forreception and transmission on a relatively high carrier frequency, suchas 13.5 MHz). One or more integrated circuits may be inserted into therecess 1710 and electrically coupled to the one or more antennas (and toone another, if one integrated circuit lends power to the other, forexample). Each integrated circuit may be electrically isolated from theother integrated circuit by encasing the circuit in a polymeric capsule.Upon insertion of the integrated circuits and coil antennas into thebase portion 1700, the grooves 1706 and 1708 and recess 1710 may befilled with a substance, such as a polymer, to create a smooth bottomportion 1700, and to seal the various elements within the base portion1700.

As an alternative, there may exist but a single groove in the buttonstyle tag, such as groove 1706. A first antenna may be wound therein.Thereafter, the antenna may be electrically isolated by deposition of amaterial, such as a dielectric material, atop the antenna, leaving onlyleads to the antenna exposed for coupling to an integrated circuit.Thereafter, another antenna may be wound in the same groove, and coupledto another integrated circuit, or to the same integrated circuit.Thereafter, the groove and recess 1710 are filled in with a material,such as a polymeric material, in order to create a smooth bottom surfaceof the button.

According to certain embodiments of a radio frequency identification tagfor identification of animals, the tag includes a first antenna 2005;and a transponder 2010 coupled to the antenna 2005. The transponder 2010including a first transmission unit 2016, first memory 2014, and firstpower circuitry 2012. The first power circuitry is configured to receivea current induced in the first antenna, and to power the firsttransmission unit and first memory. The first transmission unit isconfigured to retrieve data stored in the first memory and to transmitat least a portion of the data via the first antenna on a first carrierfrequency and on a second carrier frequency. In an embodiment, thetransponder includes a second transmission unit 2026, and second memory2024. In some embodiments, the transponder further includes a clockcircuit 2022.

It should be noted that, as used in this specification and the appendedclaims, the singular forms “a,” “an,” and “the” include plural referentsunless the content clearly dictates otherwise. Thus, for example,reference to a composition containing “a compound” includes a mixture oftwo or more compounds. It should also be noted that the term “or” isgenerally employed in its sense including “and/or” unless the contentclearly dictates otherwise.

It should also be noted that, as used in this specification and theappended claims, the term “configured” describes a system, apparatus, orother structure that is constructed or configured to perform aparticular task or adopt a particular configuration. The term“configured” can be used interchangeably with other similar phrases suchas arranged and configured, constructed and arranged, adapted andconfigured, adapted, constructed, manufactured and arranged, and thelike.

All publications and patent applications in this specification areindicative of the level of ordinary skill in the art to which thisinvention pertains.

The above specification, examples and data provide a completedescription of the manufacture and use of the composition of theinvention. Since many embodiments of the invention can be made withoutdeparting from the spirit and scope of the invention, the inventionresides in the claims hereinafter appended.

1. A radio frequency identification (RFID) tag for identification ofanimals, comprising: a first antenna; and a transponder coupled to theantenna, the transponder including a first transmission unit, firstmemory and first power circuitry, the first power circuitry beingconfigured to receive a current induced in the first antenna, and topower the first transmission unit and first memory, the firsttransmission unit being configured to retrieve data stored in the firstmemory and to transmit at least a portion of the data via the firstantenna on a first carrier frequency and on a second carrier frequency.2. The RFID tag of claim 1, wherein the transponder includes a secondtransmission unit, and second memory.
 3. The RFID tag of claim 2,wherein the first power circuitry is configured to power the secondtransmission unit and the second memory.
 4. The RFID tag of claim 3,wherein the first power circuitry, first transmission unit, and firstmemory are embodied on a first integrated circuit, and the secondtransmission unit and second memory are embodied upon a secondintegrated circuit, the first and second integrated circuits areelectrically coupled to one another for provision of power from thefirst power circuitry to the second transmission unit and second memory.5. The RFID tag of claim 4, further comprising a second antenna coupledto the second transmission unit.
 6. The RFID tag of claim 5, wherein thefirst transmission unit and first antenna are configured to transmit onthe first carrier frequency, and the second transmission unit and secondantenna are configured to transmit on the second carrier frequency. 7.The RFID tag of claim 6, wherein the first carrier frequency isapproximately 134.2 kHz, and wherein the second carrier frequency isgreater than the first carrier frequency.
 8. The RFID tag of claim 6,wherein the first carrier frequency is approximately 134.2 kHz, andwherein the second carrier frequency is at least ten times the firstcarrier frequency.
 9. The RFID tag of claim 6, wherein the first carrierfrequency is approximately 134.2 kHz, and wherein the second carrierfrequency is approximately 13.5 MHz.
 10. The RFID tag of claim 6,further comprising a body defining first and second channels configuredin a closed shape, and further defining a recess, wherein the firstantenna is wound around the first channel, the second antenna is woundaround the second channel, and the first and second integrated circuitsare housed in the recess.
 11. The RFID tag of claim 10, wherein thefirst and second channels are of circular shape.
 12. The RFID tag ofclaim 11, wherein the first and second channels are coaxial.
 13. TheRFID tag of claim 12, wherein the body is annular.
 14. The RFID tag ofclaim 10, wherein the body is polymeric.
 15. The RFID tag of claim 10,wherein the recess and first and second channels are filled by a fillingsubstance.
 16. The RFID tag of claim 15, wherein the filling substanceis polymeric.
 17. The RFID tag of claim 1, wherein the data stored inthe memory includes a number uniquely identifying an animal.
 18. TheRFID tag of claim 17, wherein the data stored in the memory furtherincludes an indicator of how large the animal is expected to be in thefuture.
 19. The RFID tag of claim 17, wherein the data stored in thememory further includes a categorization code indicating an expectedweight range of the animal.
 20. The RFID tag of claim 1, wherein, uponreceipt of an indication that the transmitted data was received by abase station, the transponder is configured to enter a period so thatthe transponder does not generate a transmission until expiration of theperiod.
 21. The RFID tag of claim 1, wherein the transponder isconfigured to pause for a delay period, prior to generating atransmission in response to a transmission from a base station.
 22. TheRFID tag of claim 21, wherein the delay period is stored in the memory,and wherein the transponder further includes a clock circuit, andwherein the transponder is further configured to witness a number ofcycles generated by the clock circuit, said number being determined bythe delay period stored in the memory, prior to generation of theresponse transmission.
 23. The RFID tag of claim 1, wherein the antennaand transponder are enclosed in a body having a surface bearing printedmatter.
 24. The RFID tag of claim 23, wherein the data stored in thememory includes a number uniquely identifying an animal, and wherein theprinted matter includes the unique identifying number.
 25. The RFID tagof claim 24, wherein the printed matter further includes a date uponwhich the printed matter was printed upon the RFID tag.
 26. The RFID tagof claim 24, wherein the printed matter further includes a date uponwhich the animal arrived at a facility.
 27. The RFID tag of claim 24,wherein the printed matter further includes a date upon which the animaldeparted from a facility.
 28. The RFID tag of claim 24, wherein theprinted matter further includes an identifying code used during handlingof the cattle at a particular facility.
 29. The RFID tag of claim 1,wherein the data stored in the memory includes a number uniquelyidentifying an animal, and wherein the transponder is configured togenerate an abbreviated number, which is the difference between theunique identifying number and another number.
 30. The RFID tag of claim29, wherein the transponder is configured to transmit the abbreviatednumber on the first carrier frequency.
 31. A method of collisionprevention for radio frequency identification (RFID) tags foridentification of animals, the method comprising: assigning each of aplurality of RFID tags a delay value; and configuring each RFID tag toreceive a query from a base station, and to respond thereto by waitingfor a duration of time corresponding to the delay value, and thenproviding a response transmission, the response transmission including aunique identification number identifying an animal associated with thetag.
 32. The method of claim 31, further comprising directing aplurality of animals, each of which are outfitted with a configured RFIDtag, through a region within radio contact of a base station; and usingthe base station to broadcast a query to each RFID tag on each animalwithin the region.
 33. The method of claim 31, further comprising:recording each delay value assigned to each RFID tag within theplurality of tags.
 34. The method of claim 33, further comprising:assigning a particular delay value for a particular RFID tag within theplurality of tags, based upon the recorded delay values, so that theassigned delay values for the plurality of tags approximately fit achosen distribution.
 35. The method of claim 34, wherein the chosendistribution is a flat distribution.
 36. The method of claim 34, whereinthe chosen distribution is a normal distribution.
 37. A method ofproviding identification of an animal, the method comprising: receivinga query from a base station with a radio frequency identification (RFID)tag in an animal; and responding to the query with a first transmissionon a first carrier frequency and a second transmission on a secondcarrier frequency.
 38. The method of claim 37, wherein the first carrierfrequency is approximately 134.2 kHz.
 39. The method of claim 38,wherein the second carrier frequency is greater than 134.2 kHz.
 40. Themethod of claim 39, wherein the second carrier frequency isapproximately 13.5 MHz.
 41. The method of claim 39, wherein a uniqueidentification number is transmitted upon the first carrier frequency.42. The method of claim 41, wherein a unique identification number istransmitted upon the second carrier frequency.
 43. The method of claim41, wherein data other than the unique identification number is alsocarried upon the second carrier frequency.
 44. The method of claim 37,wherein the query comprises a transmission that energizes the RFID tag.45. A method of identifying an animal to a base station with a radiofrequency identification (RFID) tag, the method comprising: providingthe base station with a smallest identification number assigned to anyof a plurality of RFID tags associated with a plurality of animals;receiving a query from the base station with an RFID tag in the animal,the RFID tag being assigned a unique identification number; andresponding to the received query with a reply transmission including anabbreviated identification number, which is the difference between theunique identifying number and the smallest identification number. 46.The method of claim 45, wherein the act of providing the base stationwith the smallest identification number comprises entering the smallestidentification number into the base station manually.
 47. The method ofclaim 45, wherein the act of providing the base station with thesmallest identification number comprises sending a query to the RFIDtag, the query indicating that the RFID tag is to respond with thesmallest identification number and with the abbreviated identificationnumber.
 48. The method of claim 47, wherein the abbreviatedidentification number is transmitted to the base station on a carrierfrequency of approximately 134.2 kHz.
 49. The method of claim 48,wherein the smallest identification number is transmitted to the basestation on a carrier frequency greater than 134.2 kHz.
 50. A system foridentifying animals with radio frequency identification (RFID) tags, thesystem comprising: a first base station configured to operate at a firstcarrier frequency; a second base station configured to operate at asecond carrier frequency; and a plurality of RFID tags, each tag beingassociated with one of a plurality of animals, each RFID tag beingconfigured to respond to a transmission on the first carrier frequencywith a response transmission on the first carrier frequency and aresponse transmission on the second carrier frequency, at least one ofthe response transmissions including a unique identification number. 51.The system of claim 50, wherein the first carrier frequency isapproximately 134.2 kHz.
 52. The system of claim 51, wherein the secondcarrier frequency is greater than 134.2 kHz.
 53. The system of claim 52,wherein an indicator of how large the animal is expected to be in thefuture is transmitted from an RFID tag to the second base station uponthe second carrier frequency.
 54. The system of claim 52, wherein acategorization code indicating an expected weight range of the animal istransmitted from an RFID tag to the second base station upon the secondcarrier frequency.
 55. The system of claim 51, wherein the communicationbetween the plurality of RFID tags and the first and second basestations is half duplex.
 56. The system of claim 51, wherein thecommunication between the plurality of RFID tags and the first andsecond base stations is full duplex.
 57. The system of claim 50, each ofthe plurality of RFID tags contains a surface having printed matterdisplayed thereupon.
 58. The system of claim 57, wherein the printedmatter further includes a date upon which the printed matter was printedupon a given RFID tag.
 59. The system of claim 57, wherein the printedmatter further includes a date upon which the animal arrived at afacility.
 60. The system of claim 57, wherein the printed matter furtherincludes a date upon which the animal departed from a facility.
 61. Anidentification tag for an animal, the tag comprising: a first circuitincluding a memory subunit, a power subunit, and a first transmitsubunit, the subunits electrically connected to each other; a secondcircuit including a second transmit subunit, the second circuitelectrically connected to the first circuit; an antenna connected to thefirst circuit; the power subunit of the first circuit configured togenerate an electrical current when a radio signal is received by theantenna, and delivers this current to the first transmit subunit; thefirst transmit subunit configured to transmit a first signal at a firstfrequency when it receives electrical current from the power subunit,the first signal encoding at least a first portion of any data withinthe memory subunit; the second circuit configured to transmit a secondsignal at a second frequency when it when it receives electrical currentfrom the power subunit, the second signal encoding at least a secondportion of any data within the memory subunit.
 62. The identificationtag of claim 61, wherein the first and second circuits are housed onseparate integrated circuit substrates.
 63. The identification tag ofclaim 61, wherein the second circuit is electrically connected to asecond antenna and transmits the second signal via the second antenna.64. The identification tag of claim 61, wherein the first frequency islower than the second frequency.
 65. The identification tag of claim 64,wherein the first frequency is approximately 134.2 KHz.